DESCRIPTION: Description (Adapted from Investigators Abstract): Saliva is normally inhibitory for HIV replication. One of the factors which may be involved in this is the primary defense factor in the oral cavity, namely secretory IgA. IgA is transported into secretions by secretory component (SC) synthesized by epithelial cells in the salivary glands. The expression of SC is regulated by cytokines. Since HIV infection has a profound effect on the immune system, the properties of salivary IgA antibodies of HIV infected patients will be examined including their specificity structure and function. Secondly, investigations will be initiated on the alterations of salivary cytokines or on cytokine expression by cells of the oral cavity which may influence oral manifestation of HIV infection. Third, the potential for intracellular formation of IgA anti-HIV/HIV complexes will be examined, which could lead to virus neutralization within epithelial cells in the oral cavity.